Blockchain timestamping for patent attorneys

Where this fits in your practice

Conception and diligence records. Clients are told to document when they conceived and how they worked. What they produce is usually a folder of files with editable timestamps. A hash anchored to a public ledger gives the same folder a date the client cannot adjust — which is the property that makes it worth producing.

Pre-filing evidence. The gap between "we have something" and "we filed" is where clients are most exposed and least documented. A timestamp costs a few dollars and fills it.

Disclosure logs. When a client shows an invention to a partner, an investor or a supplier, a dated record of exactly what was disclosed is useful later — for grace-period analysis, for derivation questions, and for the conversation about what was actually in the deck.

Third-party disputes. Priority arguments that fall outside the register, and design or copyright questions running alongside a patent matter.

Why clients can use this when they cannot use the alternatives

The recurring problem with dating unpublished inventions is that the conventional mechanisms need the material. A deposit service archives it. A notary sees it. An escrow agent takes custody. Each of those is a disclosure event a client's counsel has to think about.

Here the file is hashed in the client's own browser with the Web Crypto API, and only the 64-character SHA-256 hash is transmitted. There is no endpoint that accepts the file. A hash discloses nothing about contents — it is a one-way function, and there is no way back to the document from it.

That means a client can create the record without a confidentiality analysis, and without you having to advise on one.

What you can tell a client it is worth

Be conservative, because the category is full of overclaiming.

• It proves a specific file existed by a specific time and has not been altered since.
• It does not prove inventorship, authorship or ownership.
• It is not a filing, a registration or a right, and it changes no deadline.
• It is supporting evidence, whose weight is for the tribunal.

For the current state of judicial treatment, including the March 2025 Marseille decision and the position under eIDAS, see is a blockchain timestamp valid in court. It sets out what has actually been decided rather than what vendors imply, including the limits.

If you specifically need a qualified eIDAS timestamp, we are not a qualified trust service provider and cannot offer one — see the Bernstein comparison, which pairs blockchain anchoring with a qualified TSA.

How verification works, so you can check it yourself

Each certificate corresponds to one Ethereum transaction whose input data contains the payload hash as readable text.

1. Open the transaction URL from the certificate on Etherscan.
2. Select "View as UTF-8" on the input data.
3. Compare it with the payload hash in the certificate.
4. Re-hash the original file and confirm it matches the hash in the payload.

No software of ours is involved at any step, and the check does not depend on this company existing. That is the property that makes it worth putting in front of a tribunal.

Working with client volume

Firms advising several clients on this generally want the bulk pack rather than individual purchases. Certificates are bought outright, do not renew, and credits are spendable for twelve months from purchase. There is no subscription.

If you would like to discuss white-labelled certificates or bulk arrangements for client work, get in touch — this is a small operation and the person who replies can make the decision.